The present invention relates to power driven rotary machines and, more particularly, to a structure capable of supporting the outboard end of a rotating shaft without interfering with removal and replacement of a belt or other member driven by the shaft.
Power driven machines, such as saws for cutting concrete, typically use V-type drive belts to transmit power from an output shaft to a separate driven shaft. In a concrete saw, a diamond blade is carried for rotation with the driven shaft. Interaction with the belts produces transverse forces which deflect the output shaft and induce bending fatigue. This can cause the shaft to fail prematurely by breaking. Because the output shaft of an internal combustion engine is an extension of its crankshaft, it is usually not feasible to strengthen the shaft itself. Deflection of the shaft also promotes slippage of the drive belts, reducing the amount of power transmitted and shortening belt life.
Some concrete saws have been provided with an outboard bearing carried by a framework which surrounds the crankshaft to limit transverse deflection. In such cases, however, it is necessary to disassemble, reassemble and align the support each time a drive belt is replaced. This procedure is time consuming and difficult to carry out in the field, particularly under extreme working conditions.
Therefore, it is desirable in many applications to support the outboard end of a rotating shaft against transverse stresses in a manner which does not interfere with the replacement of belts or other force transmitting members engaged by the shaft.